In the images below, which is the diamond under the ideal-scope and ASET with the virtual facets outlined, the virtual facets are:
A: Returning light
B: Leaking light
C: Showing obstruction of lighting by the observer (approximated by the scopes and shown in black in the Ideal-scope and blue in the ASET)

The following section have been removed 9/7/2008. They will presented at a later date.
– How do Virtual Facets react to tilt in step cut diamonds?
– How does the virtual facet size relate to the flash size a diamond produces?
– How does the virtual facet size relate to lighting?

Lakage? Obstruction, Light Return, What’s good and what’s bad?

This will be discussed in more detail in later articles but it was suggested that I touch on it now. (Thanks Marty Haske)
All virtual facets can leak light, showing obstruction of lighting by the observer and can return light at some point.
That is not bad, it is what happens.
The key to a beautiful diamond is to do each of those things in a way people find beautiful.
Balancing all three in a pleasing manner does that.

Here is a quote from my portfolio which sums up my feelings:

“Diamond design is painting with light.
This is done by controlling the virtual facets by changing the actual facets to make the diamond look the way I want it to look.
Virtual facets can react in three ways, they can return light, they can leak light, or they can react to obstruction.
Controlling the size, shape, location and how virtual facets react under different lighting conditions and viewing distances is the key to diamond design.”

Final Notes

When writing this article I did my best to make it easy to understand and technically correct.

My goal is to arm the reader with the knowledge needed to understand my next article.

When given a choice between a full technical explanation and easy-to-understand I chose easy-to-understand.

I would like to thank those who helped edit and or contributed to this article:

Garry Holloway

John Pollard

Neil Beaty

DiaGem

Jonathan Weingarten

Marty Haske

Thank you for reading my article and a huge thank you to Andrey for allowing me the opportunity to share this with you.